A cheque for $250,000 has been presented to the UNHCR's national partner in Australia. A further $250,000 has been pledged by Vietnamese communities in Brisbane, Melbourne, Perth and Adelaide.
In March this year, on the fifth anniversary of the war in Syria, UN officials described the Syrian crisis as the biggest humanitarian and refugee crisis of our time.
Millions people have fled the country, an experience which former Vietnamese refugee, Carina Hoang, understands.
"The crisis of Syrians reminded me a lot about the crisis in Vietnam 40 years ago, but more importantly when I see unaccompanied minors or children, that just brings it very close to my heart and that's why I try to get people to open up and help" said Ms Hoang.
She started a fundraising project with other members of the Vietnamese community in Australia.
Together, they raised more than half a million dollars for the UN refugee agency.
The National Director for non-government organisation Australia for UNHCR, Naomi Steer, said the generous response is unprecedented.
"This donation which the community has pledged more than half a million dollars is, to my knowledge, the largest donation from both the Vietnamese community and indeed I suspect any of the refugee, or diaspora communities in Australia" said Ms Steer.
"It's really important that we sustain people while they are living in exile. And number one, when I speak to refugees, is security, but number two is always education. But number three is livelihood."
Half of the contribution was donated by more than 800 people in Sydney.
"I feel so sad because it makes me remember again (how it was) before I left my country," lamented Tuyet Tran, who immigrated to Australia in 1989.
"This is an opportunity for us to give something back," added Vietnamese Community NSW President Thang Ha.
